IN-CAR-NAVIGATION
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Context
…you want to build a tool that helps people plan and navigate along routes - NAVIGATION SYSTEM. This system will be used especially to plan routes and travel long distances with a car or other motorized vehicles.
Problem statement
Traveling with motorized vehicles such as cars has different constraints to a navigation system than for example walking does. How can these constraints and the problems that occur from them be solved?
Problem description with forces
Traveling with a car is much different from traveling by foot, bike and other slow means. Speed is the most important factor. It can vary from very slow in pedestrian areas up to about 200km/h on freeways.
For that reason the maps that are shown in the navigation system must be very flexible. They should range from very detailed (down to street and even house number level) to very broad (up to country and even continent level).
As there is a power supply available and therefore it is possible to mount additional devices like CD-ROM drives in a car, for in-car navigation systems these huge amounts of data can be stored easily.
Another requirement that arises from varying speed is the adaptation of zoom level to those different speeds. If a user is driving with high speed on a freeway there is no reason for displaying details like every street name. On the other hand a person who is looking for a specific address does not need to have the surrounding cities displayed. For that reason the level of zooming should automatically adapt to the current speed of the car.
One more important fact, again due to higher speed, is that a driver has to concentrate more on traffic. While a slow traveler may stop walking easily to look at an (interactive) map, a car driver can only glimpse at the map without getting in danger. For that reason in-car-navigation systems should provide different means of informing the driver about route directions or changes.
Examples
In-car-navigation systems available today come in two different ways. Either they are built-in as part of the standard equipment of new cars (or can be added later on) or they can bought as standalone systems.
An alternative to the latter are navigation systems available for PDAs such as PocketPC (e.g. Destinator 2.0 [1], SmartST [2]) or Palm (e.g. DigiMap [3]).
Solution
Therefore:
Build a special in-car-navigation system that meets all the different requirements that are special to motorized traveling.
Make the system automatically adapt to different speeds, provide means of storing larger amounts of data due to more detailed maps and implement easy usable, effective ways of instructing the driver while driving without distracting her from watching the traffic.
Diagram
References
Besides implementing the main functions of a navigation system - INTERACTIVE MAPS, PLANNING A ROUTE, ROUTE GUIDANCE- have a closer look at features that should be implemented in navigation systems generally, but that are especially important to in-car-navigation systems: VOICE GUIDANCE, SPEED-DEPENDENT AUTO-ZOOM
Literature and Links
- Destinator GmbH; http://www.destinator.de <LI>NAVMAN Mobile Limited; http://www.navman-mobile.com <LI>HEKOSOFT; http://www.digi-map.de </OL>
